Fallen Worlds supports up to 100 player empires in a 3255 x 3255 LY galaxy containing 5100 planets. At game start, a Fallen Worlds game contains a Mesophon Traders Union NPC empire and 4 small NPC warlord empires. A major nebular area with 2-5 arcs originates at the center of the map, with smaller nebular areas distributed around the periphery.
Fallen Worlds games that were started in eras before Beta 1 do not contain nebular areas.
Players' imperial capitals are placed on one of 100 special TL 7 earthlike planets that have “major” trillum deposits. These capital candidate worlds are all at least 200 LY away from one another and 100 LY away from the map edge. Capital candidate worlds can be occur in bright nebulas; these are the only earthlike planets that can exist in a bright nebula.